Urticaria or hives is a relatively common form of allergic reaction that causes raised red skin wheals. Urticaria is characterised by wheals (hives) or angioedema (swellings, in 10%) or both (in 40%). These wheals can appear anywhere on the body including face, lips, tongue, throat or ears. The condition affects an estimated 20% of the population. The itching may be mild or severe.